Set thermostat HVAC mode

Use this action to set the HVAC mode of a climate device, for example to switch a thermostat between heating, cooling, or off.

Using this action from the user interface

If you prefer building automations and scripts visually, Home Assistant walks you through this action step by step. You pick what to target, tweak a few options, and save. No YAML knowledge required.

To set the HVAC mode from an automation or a script:

1. Go to Settings > Automations & scenes.
2. Open an existing automation or script, or select Create automation > Create new automation.
3. If you’re setting up a new automation, add a trigger in the When section. Scripts don’t need a trigger. They run when something else calls them.
4. In the Then do section, select Add action.
5. Select what you want to control. Under By target (see Targets), select the climate device you want to control.
6. From the actions shown for that target, select Set thermostat HVAC mode.
7. Set the HVAC mode you want to apply.
8. Select Save.

Options in the UI

Using this action in YAML

If you work directly in YAML, or you want to know exactly what Home Assistant does under the hood, this section has the technical reference. It lists the field names you use in YAML, their types, and which ones are required.

In YAML, refer to this action as climate.set_hvac_mode. A basic example looks like this:

action: climate.set_hvac_mode
target:
  entity_id: climate.living_room
data:
  hvac_mode: heat

This sets climate.living_room to heat mode.

Options in YAML

Targets of the action

This action requires a target. The target is the object of the action. You can point the action at a single entityAn entity represents a sensor, actor, or function in Home Assistant. Entities are used to monitor physical properties or to control other entities. An entity is usually part of a device or a service. [Learn more], a device, an area, a floor, or a label, and Home Assistant will run the action on every matching climate entity behind that target.

• Entity: one specific climate entity, such as climate.living_room.
• Device: every climate entity that belongs to a device.
• Area: every climate entity in a room or area.
• Floor: every climate entity on a floor.
• Label: every climate entity that shares a label.

You can also select different target types in one action. For example, you can add a specific entity and an area as targets in the same action to run the action on both of them at once.

Good to know

• The available HVAC modes depend on the climate device. Common modes are off, heat, cool, heat_cool, auto, dry, and fan_only.

Try it yourself

Ready to test this? Open Developer tools > Actions, search for this action, fill in the fields, and select Perform action. You see what happens on your actual entitiesAn entity represents a sensor, actor, or function in Home Assistant. Entities are used to monitor physical properties or to control other entities. An entity is usually part of a device or a service. [Learn more] without writing a line of YAML.

More examples

Real scenarios where this action shows up in automations and scripts. Copy any example and adapt it to your setup.

Automation: switch to cooling on a hot afternoon

Set a climate device to cool when the indoor temperature rises above a threshold.

• Trigger: Indoor temperature rises above 26 °C
• Action: Set thermostat HVAC mode
  • Target: Living room thermostat
  • HVAC mode: cool

- alias: "Switch the thermostat to cooling on a hot afternoon"
  triggers:
    - trigger: numeric_state
      entity_id: sensor.living_room_temperature
      above: 26
  actions:
    - action: climate.set_hvac_mode
      target:
        entity_id: climate.living_room
      data:
        hvac_mode: cool

Still stuck?

The Home Assistant community is quick to help: join Discord for real-time chat, post on the community forum with the action you’re calling and what you expected to happen, or share on our subreddit /r/homeassistant.

Related actions

These actions work well alongside this one:

• Set thermostat target temperature: Sets the target temperature of a climate device.

• Set thermostat preset mode: Sets the preset mode of a climate device.

• Turn on thermostat: Turns on a climate device.

• Turn off thermostat: Turns off a climate device.